In an internal combustion engine of a piston and cylinder type, it is necessary to charge the cylinder with a fuel/air mixture for the combustion cycle and to vent or evacuate the exhaust gases at the exhaust cycle of each cylinder of the engine. In the conventional piston and cylinder type engine, these events occur thousands of times per minute per cylinder. In the conventional internal combustion engine, the rotation of a camshaft causes a spring-loaded valve to open to enable the fuel/air mixture to flow from the carburetor to the cylinder and the combustion chamber during the induction stroke. This camshaft closes this intake valve during the compression and combustion stroke of the cylinder and the same camshaft opens another spring-loaded valve, the exhaust valve, in order to evacuate the cylinder after compression and combustion have occurred. These exhaust gases exit the cylinder and enter the exhaust manifold.
The hardware associated with the efficient operation of conventional internal combustion engines having spring-loaded valves includes items such as springs, cotters, guides, rockers, shafts and the valves themselves which are usually positioned in the cylinder heads such that they normally operate in a substantially vertical position, with their opening, descending into the cylinder for the introduction or venting or evacuation of gases.
As the revolution of the engine increases, the valves open and close more frequently and the timing and tolerances become critical in order to prevent the inadvertent contact of the piston with an open valve which can cause serious engine damage. With respect to the aforementioned hardware and operation, it is normal practice for each cylinder to have one exhaust valve and one intake valve with the associated hardware mentioned heretofore; however, many internal combustion engines have now progressed to multiple valve systems, each having the associated hardware and multiple camshafts.
In the standard internal combustion engine, the camshaft is rotated by the crankshaft by means of a timing belt or chain. The operation of this camshaft and the associated valves operated by the camshaft presents the opportunity to decrease the engine efficiency to the friction associated with the operation of the various elements. Applicant's invention is directed towards a novel valve means which eliminates the need for spring-loaded valves and the associated hardware and in its simplest explanation, enlarges the camshaft to provide for spherical rotary valves to feed each cylinder. This decreases the number of moving parts and hence the friction involved in the operation of the engine and increases engine efficiency. It also eliminates the possibility of the piston contacting an open valve and thus causing serious engine damage.
Applicant's spherical rotary valve assembly in certain improvements and embodiments thereof are described in U.S. Pat. Nos. 4,953,527, 4,976,232, 4,944,261, 4,989,558 and 4,989,576. Applicant's spherical rotary valve assembly as described in the aforementioned patents eliminates the problems associated with the poppet valve assembly previously discussed.
Applicant's present invention based on the spherical rotary valve assembly relates to the porting of the intake and exhaust spherical rotary valves and the cooperation of this porting with the inlet port and exhaust port, respectively, of the cylinder head to provide for faster opening and faster closing of the inlet port and exhaust port of the cylinder head, respectively, thus providing a larger cross-sectional area more quickly in the opening phase and a reduction in the cross-sectional area more quickly in the closing phase of the valve.